Lifting jack



5 Sheets-Sheet W. B. LAKE LIFTING JACK Filed Sept. 8, 19x26 May 2l, 1 929.

May 21, 1929. w. B. LAKE LIFTING JACK Filed Sept. 8,

1926 3 Sheets-Sheet www ` May 21, 1929.

W. B. LAKE LIFTING JACK Filed sept. 8, 1512@l 5 Sheets-Sheet Patented May 2l, 1929.

NITE STTES,

VLLIAM BEAR-D LAKE,

OF BRAINTREE, ENGLAND.

LIFTING JACK.

Appiicauon filed september s, ieee, serial No This invent-ion relates Vto improvements in lifting jacks and more particularly to hydraulic lifting jacks.

The chief object of this invention is to 5 provide a lifting ack of the hydraulic type with telescopic members and packings there for which are so arranged that leakage will be positively prevented and the maximum lift be obtained.

l-leretofore in hydraulic lifting jacks it has been impossible either to obtain sufficient lift or to prevent the leakage of oil, and consequently such jacks cannot te eini ployed, for instance in a garage, lwhen it is desired to keep the car raised off its tires for a considerable time, as leakage would have the effect of gradually lowering the vehicle.

lt with the object of eliminating this defeet that the improved telescopic lifting arrangement and the packing according to present invention are designed.

A further objectis to provide means for sulpiporting the leather packing, such means being of a somewhat resilient nature and ada-1aed to prevent the percolation of the liquid through the leather.

With these and other objects in view the invention consists in arranging leather packY ings of improved shape and in arranging in contact with the packing, a wax or other like substance which is adapted to prevent leakage through the leather packing.

rlhe invention further consists in providing means whereby the hydraulic pressure will assist in maintaining the packing leathers in contact with the surfaces to be rendered fluid-tight.

The invention still further characterised in. that a cylinder containing the telescopic members is lit-ted with packing to seal the joint between the cylinder and the outer telescopic member and that the inner telescopic member is fitted with a packing to seal the joint between the telescopic members.

rlhe invention still further consists in pro viding a hydraulic jack having a cylinder adapted to receive a pair of telescopic melubers, said casing having packing adapted to seal the oint between the casing and the outer telescopic memberj and the innerpteiescopic member having packing to seal the joint between the pair of telescopic members, the arrangement being such that a greater in- 5 crease in the lifting height can be obtained than heretofore. Further, coloperating 134,227, and in Great Britain August 24, V1926.

means are provided to limit the upward movement of the telescopic members.

The invention will now be described with reference to the accompanying drawings` in which y t l n Figure l is a longitudinal sectional eleva tion of one form of telescopic lifting jack constructed according to this invention `and suitable. for garage use;

Figure 2 is a sectional plan thereof; n 1 Figure 3l is a cross-section taken on the nneaaa ot Figure l;

Figure 4 is a cross-section taken on the lineof Figure l;

Figure 5 is an enlarged sectional elevation ofthe upper portion of the jack casing showing the lower end of one of the plunge'rs therein;

`Figure 6 is an enlarged sectional elevation showing the co-operating means of the inner and outer plungers;

Figure 7 is an enlarged longitudinal sectional elevation of the valve and plunger` showing the'pl'unger in use7 the valve beingl in position for tl e lifting operation; i

Figure 8 is a similar view to Figure showing the valve operating means in use during the lowering operation;

Figure 0 is a sectional elevation of a modi tied form of hydraulic jack, suitable for or-` dinary use and for carrying on a car;

F i gure-i() is a plan thereof; Figure ll is a cross-section taken on the line o o of Figure 9;

lligure l2 is a perspective view of one end of the jack operating handle for use with the jack shown in Figures 9 and l0;

Figure 13 is a perspective iew of the outer end of the plunger rod, and l Figure le is a sectional elevation of a portion of a telescopic lifting jack showing an improved form of packing.

As shown, more particularly in Figures l to 8, a pair of telescopic plunger members l and 2 are mounted in al cylinder 23 formed vin a casing el which contains an oil or like reservoir e5 from which oil is adapted to pass to the cylinder 3 by way of a valve 6. The casing 4l is provided with wheels 7 which are rotatably mounted kand carried by a bracket 8 preferably formed integrally with the said casing Ll. To the side of the casing el are pivotally mounted at 9 a pair of bracketlike supports which are maintained in 'their adjusted position by springs or the like l1. ln Figure Qone bracket l() is shown llO lsitioned wil. jacent" to the lower end of the cylinder 3 and `is threaded -for the receptiono a threaded inV its outwardly enteiidedposition and the other bracket 1() is shown folded back on theV casiiige so that the jack can be positioned adjacent to the wheel or' the vehicle it is desired to lift. Within the casing l is mounted a tubular Vmember 12. Y This tubular mein-V ber 12 is adapted to screw intoa sleeve or the like 13 whichcarries the valve 6. rll'ils sleeve or the like 13 is mounted in a bore formed` in extension 1,4 of the wallfof the cylin der 3. The valveV end of the sleeve 13 is pom'an enlarged bore arranged adclosure member 15 which isforined withapertures 16. This closure member 15 is adapt@ ed to `form an adpistable abutment for av spring `17 which is adapted to' act onthe valve 6 and maintain it on its seating. A suitable gauze screen is positioned in front ofthe apertures 16 of the member 15. The stein *i 18 of tlie valve 6 is preferably oic triangular shape and is adapted to move in a .circular bore to permit of the ingress and 'egress of oil. The valve 6 is pieiterably. iitted or pro! vided with a washer. 4Radially arranged Cil apertures 19 are also provided in the sleeie 13 for the passage of the oil., i portion of theenlarged boreoit lthe sleeve 13 is screwthreadedat 20 for the 'reception of the threaded end 21 of a rod 22. The threaded end 21 is formed with aslot 23 to permit of the pas4 sage Vo'l the oil and a screen voi' gauzeV or other suitable material is Vpositioned adj aeent to the threaded extension 21 to' prevent'the entrance of dirt. The rod 22 is oit square or other angular shape -in cross-section and is adapted to yproject within a similar sliapec bore 25 formediii a plunger rod26 which isadaptedrto reciprocateand` rotate within the tubular member 12.. This tubular niember 12 is formed with a flange 27'wl1icli is arranged within a gland 28 threadedly mounted iii the casing` 4. @n the flange 2'? is arranged a cup-leather orV like washei29 and on'tliisY washer 29 is mounted awinetal washer 30. rlhe arrangement is such that,

leakage of oil will be prevented during the forward movement or" therplunger 26. @n

the washer 8O is adapted to seat one end ol:V

a spring 431 which has its other endl seated in a V-sliaped washer 32 and abutting upon' this washer 32 a metal washer 33 which is adapted to bear against another cup-leather washer 34g mounted inthe gland 28;' This latter washer 34 is `adapted to prevent the iiitalre of air during the movement of the plunger 26. The gland 28 is formed with apertures 35 to permit of the passageof oil from the oil reservoir This reservoir 5 is adapted to be filled-with' oil through the apertures in the casingV 4;. This aperture is closed by a screw-threaded cap BG'iformed with an air vent or thelilre 37. rlie lower end of the plunger 1 is fitted with a cupV` leather washer or the like 38 which ismaintained in position by a nut' member or Ythe like 39 screwed on to a threaded extension of the plunger 1. Adjacent to the lower end ot the plunger 1 is lcut a groove l0 within which is arranged ia split expansion ring 41. ltllieii the plunger 1 is in its highest position, tliis'ring llleirpands and enters an aiinular groove l2 cut in the outer plunger inein-` ber 2 and it will be 'seen that this arrangement prevents the member 1 from being,

forced. out of the'plunger member 2. Thelowei wall of the annulargroove 42 is out away or inclined vat i3 `so as to contract the expansion, ring l1 and permit the downward nic-i ement of the plunger 1 when the weight 'p carried `by the crutch head lll is lowered. Theciutcli head lli is preferably adjustably mounted in thepliinger 1 in the well-known manner, the adjustment being effected by means of a pin 45 adapted to be positioned one ofja plurality of apertures 46 Yformed A i rod l? carried by the crutch head 4A, the pin l5 being arranged transversely and adapted to seat on the upper end of the plunger 1. A suitable washer 48 is arranged onthe upper end of t ie plunger 2te further prevent leal;- age between the plungers 1 and 2.y The lower end of the plunger memberA 2 is also formed with an annular groove i9 which is cut away or inclined at .-50 in a similar manner to the vgroove 42. lNithin this y'groove l2 is adaptedito be positioned a split ring 51 when theV plunger 2 is in its highest position and thus limit the outward movement ofthe plunger 2. The `split ring 51 is normally 'arranged within a groove 52 cut in the cylinder 3v and the ari'aiigementis suoli that'the split ring 51 will be expanded and lie in the groove 52 when t-he plunger. 2- is lowered by the lll) height to giveconsiderably greater lift than Y heretofore.

To the outer end of the plunger rod 26 is Y pivoted at 56 a connect-ing rod member 57 which is pivotally mounted in any suitable manner in the lower forked end 58 of an operating lever 59 which is tulcruined on a fulcrum pin 60. rllhis fulcrum pin 60 is carried in' a forked bracket 61l which is adapted to form a base for the operating lever 59. This forked bracket 61 is also secured to thefouter end oi' a member 62 which is connected at its other Vend to the casing 4:; thus the iulcrum portion ofthe jack is maintained-'rigidly in spaced relation to the casing portion of the jack. The lever "59 is preferably provided with an auxiliary iiuicrum 63 and is soarranged that it may be adjusted in an angular position, ior instance, the lever 59 may be arranged in its normally vertical position by placingv a pin 64 through an aperture 65 cut in a plate 66 carried by the forked end 58 or it may be arranged in an angular normally inclined position by placing the pin 64 through the aperture in the lever 59 and through an al'ierture 67 in the plate 66, when it is inconvenient for the lever 59 to be in a normally vertical position, such as when the jack has to be positioned a considerableA distance under the car. The upward movement of the lever 59 is limited by a plate 6h secured to the il'orkcd bracket 61 and adapted to cngapc the forked end 53 oi the operating lever F9. To the outer end ot' the connectingr rod member 57 is secured a handle member 69 whereby the plunger rod 26 may be rotated in the manner to be hereinafter described. The outer end of the connecting' rod 57 rotatably mounted in the forked end 58 of the operating lever 59 through the medium of a pair ot nut members 7 (l.`

In operation, and assumingr that the jack is `in its lowest position with the crutch .head all positioned under. tor instance, an axle ot a vehicle, it is desired to litt and the operating lever 59 is in a vertical position, the said lever 59 ismoved downwardly to 'torce the plunger 26 into the tubular member 12. lt will be obvious that by reciprocating Vthe plunger 26 through the medium oit the operating lever 59 oil `from the reservoir 5 will be forced past the valve 6 into the cylinder 3 by way of the aperture 23 in the threaded member 21. and apertures 19 in the sleeve 13. During this operation the oil will be drawn in from the reservoir 5 by way of the ports and will be forced into the cylinder 3 to raise the plunneis 1 and 2 and the crutch head lll/Then the plungers are fully raised the split ring 41 in the plunger 1 will expand and entcr'the annular groove 4t2 cut in the outer plunger 2 and the split ring' 51 normally positioned in the groove 52 of the cylinder 3 will contract and enter the groove i9 cut in the outer plunger 2. lWhen it is desired to lower the jack the opera-ting` lever 59 is returned to its normal. vertical position and the handle member 69 is turned to partially rotate the plunger 26. This partial rotation of the plunger 26 will also rotate the rod 22 and turn the threaded end 21 in the sleeve 13 and thus the forward end oi the rod 22 willen- ,cjage on the valve stem 13 and force the valve 6 oit its seating against the action ot the springl 17. The oil in the cylinder 3 will now return by way of the ports 23 and 35 and the tubular member 12' to the reservoir 5. The lowering' speed of the jack can be varied aceordingto the amount the valve 6 is moved oit its seating and the lowering will he assisted by the weight carried by the crutch head 4l. "When ythe lowering operation 1s complet-ed the handle 69 is turned back to itscan 'flow from the reservoir 5 through the port 35. The forward movement oi the plunger will force the oil past the valve` 6 into the cylinder 3 and the sequence of operations will be repeated when it is required to again use the jack. The wheels 7 on the for ward end oi the jack will assist thc positioning` of the jack under thecar and it will be seen that the jack will be adequately supported when one or both ot the brackets 10 are in their outward position.

ln a modified construction as shown in Figures 9 to 13, and when the invention is applied to a jack suitable for ordinary use and for carrying on a car, the casing` 4, is formed with a biturcated bracket 71 which is adapted to carry a tulcrum pin 72 on which is mounted a handle socket 73. This operating iandle socket 73 is formed with a pair.

of downwardly extending' arms 74- on which are mounted one end of connecting links 75. The other ends of the connectinglinks 75 are connected to a sleeve 76 which is mouned on the outer end ofthe plunger rod 26 which is adapted to reciprocate within the casing` 4 and operate in a similar manner to that previously described. The casing;` portion 4 ot the jack and the plunger members 1 and 2 will not be `further described as the construction and operation is similar to the previous construction. 1Within thesocket 73 is adapted to be placed the lower end rof an operating handle 77 of any suitable'length. The lower end operating` handle or lever 77 is formed or provided with a bayonet joint vor iitting;` 78 which is adapted to co-operate with a bayonet fitting.;` 79 formed or provided in the interior of the socket 73. The arrangement is such that `when the handle 77 is forcedrinto the socket 73 and givena partial rotation; the said handle 77 will be detachably locked in position` in the co-operating bayonet .fittings by the action of a spring 8O disposed within a recess formed in the lower end of the said socket 73. The extreme lower end of the handle or lever 77 is formed lwith another bayonet socket littinc" 81 which is adapted to co-operate with a. socket pin fitting' 82 secured on the outer end of the plunger rod 26.

ln operation. and when it is 'desired to raise this modified form of jack, the casing' l is positioned under the vehicle and thel crutch head 4:4 is arranged under the portion of the vehicle to be lifted. The operating handle lever 77 is pushed into the handle socket 73 against the action of a sprinp- 8O lll() lIU ` struction.A

i andpartially rotated so that the bayonet it- Y tings 78 land 79 cooperate to'hold the handle 7 7 in position. Upon the downward and upward movement .of the handle, 77 Vthe y plunger Qwill be reciprocated through the handle lever 77 Vis forced inwardly against the action of the springSG and partially rotatedto unlockthe co-operating itments 7 8 and 79 and permit of the Withdrawal of the said handle. The extreme lower end ofthe handle or lever 77. is nowrinserted in the socket Apinlitting 89 on the plunger'rod 26 and partially rotated to rotate the plunger i rod 26. This rotation of the plunger rod 26 .will act in a similar manner to that previously described in connectionwith the iirst construction and move the `valve@ oil its seating andI thus the V4weight carried by ther crutch khead le will be loweredV automatically. In this modified construction, the wheels 7 and i supporting brackets 10 are omit-tech but it will be understood that they may be providedif desired. Y s Y Referringto the modilied orm of, packing shown in Figure 14; of the drawings, it will be seenlthat the jack casing-or cylinder 3 is enlarged at its upper end to receive packing means vwhich are adapted to prevent leakage orp fluid past the'outer telescopic member `or sleeve ram 2 in which is mounted the inner telescopic member or inner ram 1 which, is

fitted at its lower end with packing means to prevent leakage Voit fluid between the tele'-V scopic members 1 and 2. lna threaded re- Y cess 'formed in the upper end of the cylinder 3 `is adapted to screw an upper gland nut 86 which is formed internally with a groove or the-like 87 of preferably two depths. In the deeper groove 87 is mounted a leather washer or scraper S8 which is adapted to con`-V tact with .the sleeve' ram 2. VBelow this up per gland nut 86 is positioned a leatherV 89 of annular shape and below this support .is

mounted a `hat leather of leather or othery vsuitable material.

This hat leather` 90 is of substantially LV shape in cross-section. `113elow this hat leather 90 is positioned a lower hat leather support 91. Between the leathers 89 and 90 is disposed an annular sheath of wax or other 4suitable like material 9210i substantially triangular shape in cross-section,

and betweenthe leathers 90 and 91 is disposed another wax annular sheath 93. Below the leather 91 and kscrewing into the base of the recess 85, is a lower gland'nut 94,

which is inclined at its inner edge to permit any leakage of pressure to 91 and press the same upwardly. The leather 91 is so shaped and clamped between the gland nuts 86 and 94 that it is adapted to act on the vertical portion of the` hat leather 90 and press the saine against the sleeve ram 2. A l leather seat95 is provided between the lower. gland nut 9i and 'thebase oli the recessr,

formed in the casing. The lower surface of act on the leather the gland nut 9land the base oi the' recess.V Y,

85 are formed with circumferential andop! positely arranged J4-shaped grooves or re- 1 Acesses 96 to make a lirm seating iorthe seating leather 95. The lower end'oii the sleeve ram 2 is formed with an enlarged iange97 which is adapted to abutagainst the lower leather seat 95 when the sleeve ram 2 is in its high position. Thus leakage of lluid such as oil which is adapted to raise the rams will be effectively prevented. i ,Y t

The lowerend f the inner ram 1 is 'lo 'ined with a threaded extension 98 and on this threaded extension is adapted to screw a rain head 99 which is adapted to retain'against the bottom of the Vinner ram Aan annular shaped leather washer100 anda leather cupV L washer 101, which latter is or' L shape in crosssect-ion. Between the ramhead 99 and the cup vwasher 101, which latter is ot leather, isV positioned a wax proofing sleeve 102 which is adapted to press the cup washer 101 outwardly against the inner wall ofthesleeve ram 2. The ram head 99 is formed with apertures .103

through 'which oil is adapted to Vpass to the wax sleeve 102, and thus the pressure of the oilv will further tend to force the cup leather 101 outwardly. i i

0n the upper end of the sleeve ram 2 is adapted to screw a cap or nut 104i whiclris preferably formed with a knurled edge 105. This cap 104Cv is adapted to keep in position ico on the upper end of the sleeve ram 2.a scraper leather washer 106 and a hat leather washerl 107. This hat .leather washer 107Y is of L shape in cross-section. and the -grooye for the verticalportion of this hat leather washer 107 is extended and enlarged at 108 for the rece tion of any oil which may leak between the rams 1 and 2. Such leakage of oil will tend to press the vertical portion of the hat leather washer 107 against the inner ram 1. lower edge of the washer 107 is preferably tapered so as to render the said edge'more flexihle. The lower edges of the other L shaped washers 90 and 101 may be also tapered for a similar purpose if so desired. lt will be seen that the wax proofing is so arranged that it will preventthe oil from percol ating through the leather washers. Further, the washers are soishaped and disposed that the internal pressure of the oil will tend to force them in such a manner to renderthe joints fluidtight. Y Y

In operation and when oil ,vor other fluid is The forced into the cylinder 3 by any suitable means the outer ram 2 will be raised until its flange 97 presses against the lower leather 95. Further pressure of the fluid will move the inner ram l upwardly in the other ram 2 and a suitable stop will be provided to limit the upward movement of the inner ram 1.

It will be seen that by the invention there is provided a hydraulic jaelr for garage or ordinary use which will have a higher lift than is obtained by hydraulic acls at pres entconstructcd and further the lift may be increased by providing more than two telescopic members.

Reference is made to applicants co-pending application tiled September 7, 1926, Serial No. 134,081, for claims directed to subject-matter specifically described but not claimed herein.

1. A lifting acl of the hydraulic type comprising a power cylinder, a single valve located at one side of the cylimler and simultaneously controlling the admission of fluid to and its exhaust from the cylinder, and a pair of telescopic members slidably mounted in the cylinder, said telescopic members in collapsed relation extending to si'lbstantially the bottom of the cylinder and below the valve whereby, through the length of such telescopic members thus accommodated, the jack is capable of a minimum height in collapsed relation. and a maximum height in extended relation.

2. A lifting jack of the hydraulic type comprising a power cylinder, a single valve located at one side of the cylinder and simultaneously controlling the admission of fluid to and its exhaust from the cylinder, a pair of telescopic members slidably mounted in the cylinder, said telescopic members in collapsed relation extending to substantially the bottom of the cylinder and below the valve, and cooperating means carried by the wall. of the cylinder near its upper end and the wall of the outermost telescopic member near its lower end to limit the extended movement of such telescopic member relative to the cylinder.

3. A hydraulic jack including a cylinder formed above its lower end with an opening for the inlet and outlet of the fluid pressure, a single valve for controlling this opening, and a plurality of telescopic members mov able in the cylinder, the outermost of such members being in hollow cylindrical form, the unobstructed wall of the fluid cylinder ol the jack permitting collapsing movement of the telescopic cylinder to a position just free of contact with the bottom of the fluid cylinder and past the opening in the wall of the fluid cylinder, whereby to permit of telescopic members of maximum length with minimum projection beyond the fluid cylinder in their telescoped relation to thereby `provide a jack having minimum height when collapsed with maximum height when extended.

4. A hydraulic jack having a pressure fluid cylinder formed with a fluid opening, telescopic members movable in the cylinder and relative to each other under fluid pressure, the outermost member being formed near its lower end with an annular groove, and a spring member arranged in the wall of the cylinder near the upper end thereof to engage in said groove to limit the relative outward movement of the telescopic member.

5. A hydraulic jack having a pressure fluid cylinder formed with a fluid opening, telescopic members movable. in the cylinder and relative to each other under fluid pressure, the outermost member being formed near its lower end with an annular groove, and a split spring ring mounted in the wall of the cylinder and adapted to engage in said groove to limit therelative outward movement of the telescopic member.

6. A hydraulic jack having a pressure fluid cylinder formed with a fluid opening, telescopic members movable in the cylinder and relative to each other under fluid pressure, the outermost member being formed near its lower end with an annular groove, and a split spring ring mounted in the wall of the cylinder and adapted to engage in said groove to limit the relative outward movement of the telescopic member, said telescopic member being formed to extend the ring into non-active position in the inward movement of the telescopic member.

7. A hdraulic jack havingv a pressure fluid cylinder formed with a fluid opening, telescopic members movable in the cylinder and relative to each other under fluid pressure, the outermost member being formed near its lower end with an annular groove, a spring member arranged in the wall of the cylinder near the upper end thereof to engage in said groove to limit the relative outward movement of the telescopic member, and packing carried by the cylinder near the outer end thereof to seal the juncture between the cylinyder and said outermost telescopic member.

In testimony whereof I have hereunto signed my name.

WILLIAM BEAR-D LAKE. 

